Portable devices exist that provide radio frequency (RF) receiver functionality and RF transmitter functionality. In addition, prior systems have used transmit antennas and receive antennas. For example, some portable devices have an FM transmitter and an FM receiver, as part of the same device. Many portable devices, however, have significant restrictions in the space available for antenna structures. These space constraints make it difficult to provide an antenna of appropriate size for transmission and reception of RF signals, particularly in the FM audio broadcast frequency spectrum (e.g., about 76 to 108 MHz).